کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
34661 45038 2014 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Stabilizing hyperactivated lecitase structures through physical treatment with ionic polymers
ترجمه فارسی عنوان
تثبیت ساختارهای لسیتاز بیش از حد فعال شده از طریق درمان فیزیکی با پلیمرهای یونی
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی بیو مهندسی (مهندسی زیستی)
چکیده انگلیسی


• Lecitase Ultra has been immobilized via covalent attachment.
• Detergents improve enzyme activity while reduce enzyme stability.
• Coating of the enzyme with PEI improves 3-folds the enzyme activity.
• Coating of the enzyme with PEI in presence of SDS improves enzyme activity by 50 folds.
• The catalytic Ser is more accessible to the medium after this protocol.

Lecitase Ultra has been covalently immobilized on cyanogen bromide cross-linked 4% agarose (CNBr) beads, maintaining 70% of the initial activity. The activity of the immobilized enzyme was improved in the presence of Triton X-100, sodium dodecyl sulfate (SDS), and cetyltrimethyl ammonium bromide (CTAB) (e.g., up to 800% when using CTAB). However, CTAB and Triton X-100 presented a negative effect on enzyme stability even at low concentrations, and SDS cannot be used for a long time at 1% concentration. To maintain the hyperactivated conformation of the enzyme in the absence of detergent, ionic polymers were added during incubation of the immobilized enzyme in the presence of detergents. Coating the immobilized enzyme with polyethylenimine in aqueous buffer (PEI) produced a 3-fold increase in enzyme activity. However, in the presence of 0.1% SDS (v/v), this coating produced a 50-fold increase in enzyme activity. Using PEI and 0.01% (v/v) CTAB, the Lecitase activity decreased to 10%. Using irreversible inhibitors, it could be shown that the PEI/SDS-CNBr-Lecitase preparation allowed its catalytic Ser to be more accessible to the reaction medium than the unmodified CNBr-Lecitase.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Process Biochemistry - Volume 49, Issue 9, September 2014, Pages 1511–1515
نویسندگان
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